Grinding machine having cross feed table and wheelslide



July 6, 1965 P. A. GROBEY 3,192,674

GRINDING MACHINE HAVING GROSS FEED TABLE AND WHEELSLIDE Filed Sept. 5. 1961 4 Sheets-Sheet 1 INV ENTOR. 7'2l/ /Z 70 Ze July 6, 1965 P. A. GROBEY 3,192,674

GRINDING MACHINE HAVING CROSS FEED TABLE AND WHEELSLIDE Filed Sept. 5. 1961` 4 Sheets-Sheet 2 INVENTOR. fzf/ /7 fae?.

P. A. GROBEY July 6, 1965 GRINDING MACHINE HAVING CROSS FEED TABLE AND WHEELSLIDE Filed Sept. 5. 1961 4 Sheets-Sheet 4 INVENTOR.

. i @Nfl/4' United States Patent() 3, V)2,674 GRIIDEJG MACHEJE HAVLNG CRSS FREE ANB) WHEELSMEE Paul A. Graf-hey, Springileld, Wt., assigner te Bryant @inici-:ing Grinder Company, Springheld, Vt., a corporation of Vermont Eiied Sept. 5, 1961, Ser. No. 1313,32? d Cian-ns. S21-5i?) This invention relates to universal grinders, and more particularly to grinders of the manually operated tool room type capable of grinding to extreme accuracy over a wide range of sizes and types of parts.

It is an object of the invention to provide an improved universal grinder of this nature which permits the cross feed mechanism to be attached to the bed, thus making manual cross feed during the reciprocal grinding stroke simpler and more accurate.

1t is another object to provide an improved universal grinder having the above characteristics, which minimizes grinding inaccuracies at the ends of the stroke during oscillating traverse of the wheelslide.

Other objects, features, and advantages of the present invention will become apparent from the subsequent description, taken in conjunction with the accompanying drawings, in which:

FGURE 1 is a schematic View illustrating the principles of the invention;

FGURE 2 is a perspective view of a suitable embodiment of the invention;

FEGURE 3 is a fragmentary elevational view from the front of the machine showing the mounting of the cross feed table on the bed;

4 is a left end view of the wheelslide showing the manner in which it is supported by the cross feed table as Well as the connecting means for the traverse cylinder; and

FGURE 5 is a right hand end elevational View of the wheelslide and cross feed table showing further details of the manner in which they are supported.

In general terms, the illustrated embodiment of the invention comprises an elongated base having a workhead at one end capable of being transversely positioned and swiveled for taper or rotary face grinding. A cross feed table is mounted adjacent the other end of the bed on Ways transverse thereto. The longitudinal slide table or wheelslide for carrying the wheel spindle to and from the Work is mounted on longitudinal ways carried by the cross feed table. With this arrangement, the manual and power controls for the cross feed table remain stationary during the reciprocal grinding stroke of the wheelslide. Moreover, since the cross feed table is not reciprocated with the wheelslide, the total reciprocating mass is greatly reduced and the length of the vertical connection between the piston rod of the hydraulic traverse cylinder and the Wheelslide is substantially shortened as compared with conventional constructions.

Referring more particularly to the drawings, FIGURE 1 shows in schematic fashion the inventive principles illustrated by the remaining gures. The elongated bed of the grinder is generally indicated at 11, and the cross feed table generally indicated at 12 is supported directly by bed 11 on ways generally indicated at 13 transverse to the longitudinal extent of the bed. A longitudinal slide table or wheelslide generally indicated at 14 is supported by sassari jatented July 6, 1965 cross feed table 12, the wheelslide being reciprocable in the direction of longitudinal extent of the bed and being supported by longitudinal ways generally indicated at 15. A bracket 16 mounted on wheeslide 14 carries a Wheel spindle 17 on which is mounted a tool T in the form of a grinding wheel.

Because of the mounting of cross feed table 12 directly on base 11, the cross feed mechanism, generally indicated at 1S, may be mounted directly on the front of bed 11. This mechanism will not reciprocate with wheelslide 14 and will therefore be readily accessible during operation. Moreover, the vertical distance D between the axis of spindle 17 and the motor for reciprocating the wheelslide will be relatively short, as seen in FIGURE 1. The motor comprises a hydraulic cylinder 19, one end of which is pivoted at 21 to cross feed table 12. ,The outer end of piston rod 22 is pivotally connected to a downwardly projecting post 23 secured to wheelslide 14. Motor 19 will not have to counteract the inertia of cross feed table 12 and its associated parts at the ends of its reciprocating or oscillating stroke, and the relatively short distance D will minimize inaccuracies due to the momentum of wheelslide 14 and its associated parts when the traverse stroke is reversed.

The relative positions of the machine components are seen in FGURE 2. Cross feed table 12 and wheelslide 14 are mounted adjacent the right end of the machine in this figure, the workhead 245 being mounted at the left end of base11 by means of a sub-plate 25 pivote-d on a work table 25. Table 2 is movable transversely of bed 111 by means of a handwheel 27, and the pivotal mounting of sub-plate Z5' permits the svork spindle to be angularly adjusted with respect to the grinding wheel spindle. The work spindle is driven by a reversible motor 2S mounted on the workhead, grinding Wheel spindle 17 being driven by a motor 29 mounted on bracket 16. Features and elements of the machine unnecessary to an understanding of the invention are not described. However, it will be understood that in normal operation the work carried by Workhead 24 Will be slowly rotated with rapidly rotating grinding Wheel T in contact therewith, the grinding wheel being fed into the workpiece surface to be ground by cross feed mechanism 18 after having first been positioned opposite the surface to be ground by traverse of wheelslide 14 and Work table 26.

The traverse of wheelslide 14 is controlled by a handwheel 31 mounted on cross feed table 12 to the right of cross feed 18. When this handwheel is pulled forwardly (out of the paper in FIGURE 2) a pinion (not shown) on its shaft will engage a rack 32 secured to wheelslide 14. At the same time, a bypass valve (not shown) will be opened rendering slide cylinder 19 inoperative for manual traverse. Pushing back on handwheel 31 will disengage the manual traverse and activate the cylinder.

A pair of adjustable reversing stops 33 and 34 are mounted on the front of wheelslide 14. These stops may be set to control the position and length of the reciprocal grinding stroke. A traverse control lever 35 is mounted on cross feed table 12 and has a button (not shown) engageable by one or the other of these stops on the moving slide to cause the lever to shift position. This will reverse the hydraulic pressure to wheelslide cylinder 19, thus reversing the direction of wheelslide movement. Lifting handle 3S will lower the button to operating position between the reversing stops. The speed of the slide is con- Q trolled by a throttle lever 36 to the left of the traverse control lever.

Cross feed mechanism 1S comprises a feed case 37 mounted on the front ledge of bed 11. A handwheel 38 is mounted on the front of the case 37, and a pinion (not shown) on the inner end of the handwheel shaft within the feed case engages a gear keyed to a feed screw nut (these parts being also notI shown). The nut is rotatable but cannot move endwise, being rotatably mounted within feed case 37. A cross feed screw (not shown) engaging the nut is keyed to the feed case to preventI rotation but permit endwise motion. The screw bears against a hardened button 39 on the face ofthe Cross feed table 12 as seen in FIGURE 3. Rotation of the cross feed nut by handwheel 3? through the pinion and gear will produce transverse feed and back-off motion of the feed screw. A piston rod of a hydraulic cylinder (not shown) exerts force against the rear of the cross feed table to hold it rmly against the feed screw.

The manner in which cross feed table 12 is mounted on bed 11 is seen best in FIGURES 3 to 5. A left hand or controlling way 4i and a pair of right hand ways 42 and 43 are mounted on base 11. Way it consists of a heavy, rectangular section steel bar fastened transversely to the bed. The right hand ways consist of two hardened and ground steed plates attached to the bed at the front and rear right hand corners.

The vertical load is carried by four bearings 44, 45, 46 and 47. These are recirculating antifriction bearings, bearings 44 and 45 are heing supported by way 4E, bearing 46 engaging way 42, and bearing 47 engaging way 3. These bearings are all secured to the underside of cross feed table 12 within transversely extending recesses 48 and 49 provided for this purpose.

. A pair of way bearings 51, one of which is visible in FIGURE 3, engage the right hand side of controlling way bar 41. These are also recirculating antifriction roller bearings. rl`wo grease-packed double row radial ball bearings 52 and 53 engage the left side of way bar 41 opposite bearings 5l. Bearings 52 and 53 are mounted on opposite ends of a preload bar Se, seen in FIGURE 4, which extends parallel to way il on the left hand side thereof. The preload bar is held in position by two pins 55 and 56 protruding from cross feed table 12 and loosely disposed within two holes in the bar. A hollow set screw 57 in a lug 5% on the underside of the cross feed table 12 bears against the center of the left side of preload bar 54. Tightening screw 57 against the bar exerts force against the side of way 41 at the points of Contact of bearings 52 and S3. This will draw cross feed table A12 to the left in FIGURE 3 so that the bearings are under load between the right side of bar 41 and way groove 4S, thus insuring rigidity and stability of the cross feed motion.

A pair of parallel cast iron ways 59 and 61 are mounted on the forward and rear portions of cross feed table 12 respectively for supporting wheelslide i4, these ways being machined longitudinally of the table and being disposed on opposite sides of a longitudinally extending recess 62 formed in the upper portion of cross feed table 12. The vertical load is carried by four bearings comprising two pairs 63 and 64, bearings 63 engaging forward way 59 while rear hearings 64 engage rear way 61. The two bearings of each pair are located at opposite ends'of wheelslide 14. A pair of bearings 65 and 66 is located at each end of wheelslide 14 facing the front and rear respectively of way 59. The four bearings 65 and 66 absorb transverse thrust loads such as grinding pressure.

A post 67 is secured'to cross feed table 12 within groove 62 at the right hand end of the table, when viewed from the front of the machine. Hydraulic cylinder i9 is pivotally connected to post 67 by pivot 21, the cylinder extending toward the left end of the machine. Downwardly extending post 23 is secured to the left end of wheelslide i4 and is pivotally connected to piston rod 22. Because of the disposition of cross feed table l2 between wheelslide 14 and bed 11, the vertical distance between cylinder i9 and the centerline of wheel spindle 17 will be relatively short.

In operation, wheelslide 14 will first be manually traversed by handwheel 31 to the left to check clearance of wheel T entering the workpiece bore. The wheelslide reversing stops 33 and 34 will be set, and the wheelslide 14 moved to the right after which manual traverse will be disengaged by pushing handwheel 31 rearwardly away from the operator. Work rotation and tool rotation will be started, and hydraulic movement of wheelslide 14 to the left initiated by moving traverse control handle down and to the left, and fully opening throttle 36.

Wheelslide 14 will move to the left, and when left hand reversing stop 33 has passed under traverse control lever 35, this lever will be lifted to position it between the reversing stops. The throttle handle 36 will be adjusted to the desired grinding traverse speed, and the tool will be fed toward the work either manually by means of handwheel 3S or by engaging a power feed, not described.

To stop grinding, the grinding wheel will be backed off from the work with feed handwheel 33. Traverse control handle 35 will be depressed and moved to the right, being held in that position until wheelslide i4 has reached its extreme right hand position.

While it will he apparent that the preferred embodiment of the invention disclosed is well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modication, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. In a grinding machine, an elongated bed, a work;

head mounted adjacent one end of said bed, a cross feed table mounted adjacent the other end of said bed for transverse movement, mounting means for said cross feed table comprising at least two parallel flat longitudinally spaced transverely extending ways on said bed, antifriction bearings between the underside of said cross feed table and said ways, a cross feed control mechanism mounted on said bed between said ways and engageable with said cross feed table for shifting the cross feed table in said transverse direction, a wheelslide mounted on said cross feed table for longitudinal movement, mounting means for said wheelslide comprising a pair of parallel at transversely spaced longitudinally extending ways on said cross feed table, bearings carried by the underside of said wheelslide and engageable with said ways, a recessed portion on said cross feed table between said ways, grinding wheel mounting means on said wheelslide, and a reciprocable traverse motor disposed within said recessed portion and connecting said cross feed table and wheelslide. u 2. In a grinding machine, an elongated bed, a workhead mounted adjacent one end of said bed, a cross feed table mounted adjacent the other end of said bed for transverse movement, mounting means for said cross feed table comprising at least two parallel at longitudinal spaced transversely extending ways on said bed, antifriction bearings between the underside of said cross feed table and said ways, a cross feed control mechanism mounted on said bed between said ways and engageable with said cross feed table for shifting the cross feed table in said transverse direction, a wheelslide mounted on said cross feed table for longitudinal movement, means for manually-traversing said wheelslide comprising a handwheel mounted on said cross feed table and a rack mounted on said wheelslide, and grinding wheel mounting means on said wheelslide.

3. In a grinding machine, an elongated bed, a cross feed table, at least two paralleli'lat longitudinally spaced transversely extending ways on said bed, anti-friction bearings carried by the underside of said cross feed table and resting on said Ways, a wheelslide, longitudinal Ways on said cross feed table supporting said Wheelslide, a recessed portion on said cross feed table between said ways, and a reciprocating traverse motor disposed between said cross feed table and wheelslide within said recessed portion.

4. In a grinding machine, an elongated bed, a workhead mounted adjacent one end of said bed, transverse Ways adjacent the other end of said bed, a cross feed table mounted on said ways, a feed case mounted on the forward side of said bed, a handwheel and handwheel shaft mounted on said feed case for transversely shifting said cross feed table on said Ways, a pair of parallel flat transversely spaced longitudinally extending ways on said cross feed table, bearings carried by the underside of said Wheelslide and resting on said last-mentioned Ways, a longitudinal recessed portion between said wheelslide and cross feed table, a reciprocating traverse cylinder in said recessed portion and connecting said cross feed table and Wheelslide, a Wheel spindle mounted on said Wheelslide, and a manual traverse handwheel mounted on said cross feed table and adapted to be engageable with said Wheelslide.

References Cited by the Examiner UNITED STATES PATENTS 1,599,245 10/25 Gilbert 51-261 2,097,429 11/3 7 Blood.

2,118,967 5/38 Curtis 51-l66.6 X 2,230,442 2/41 Arms 308-6 2,592,071 4/52 Russell 51-291 2,622,939 12/52 Ljunggren 308 2,830,409 4/58 Northcutt a- 51-50 2,952,949 9/60 Maker 51-50 FOREIGN PATENTS 807,667 7/51 Germany.

LESTER M. SWINGLE, Primary Examiner.

20 FRANK H. BRONAUGH, JOHN C. CHRISTIE,

J. SPENCER OVERHOLSER, Examiners. 

4. IN A GRINDING MACHINE, AN ELONGATED BED, A WORKHEAD MOUNTED ADJACENT ONE END OF SAID BED, TRANSVERSE WAYS ADJACENT THE OTHER END OF SAID BED, A CROSS FEED TABLE MOUNTED ON SAID WAYS, A FEED CASE MOUNTED ON THE FORWARD SIDE OF SAID BED, A HANDWHEEL AND HANDWHEEL SHAFT MOUNTED ON SAID FEED CASE FOR TRANSVERSELY SHIFTING SAID CROSS FEED TABLE ON SAID WAYS, A PAIR OF PARALLEL FLAT TRANSVERSELY SPACED LONGITUDINALLY EXTENDING WAYS ON SAID CROSS FEED TABLE, BEARINGS CARRIED BY THE UNDERSIDE OF SAID WHEELSLIDE AND RESTING ON SAID LAST-MENTIONED WAYS, A LONGITUDINAL RECESSED PORTION BETWEEN SAID WHEELSLIDE AND CROSS FEED TABLE, A RECIPROCATING TRAVERSE CYLINDER IN SAID RECESSED PORTION AND CONNECTING SAID CROSS FEED TABLE AND WHEELSLIDE, A WHEEL SPINDLE MOUNTED ON SAID WHEELSLIDE, AND A MANUAL TRAVERSE HANDWHEEL MOUNTED ON SAID CROSS FEED TABLE AND ADAPTED TO BE ENGAGEABLE WITH SAID WHEELSLIDE. 